Answer:
Step-by-step explanation:
Use Pythagorean.
The width and height are the legs and the diagonal is the hypotenuse of the right triangle.
Look at the diagram and apply Pythagorean theorem
[tex]\\ \tt\hookrightarrow x^2=65^2-25^2[/tex]
[tex]\\ \tt\hookrightarrow x^2=4225-625[/tex]
[tex]\\ \tt\hookrightarrow x^2=3600[/tex]
[tex]\\ \tt\hookrightarrow x=60cm[/tex]